For debugging, object_err() prints free pointer of the object. However, if check_valid_pointer() returns false for a object, dereferncing `object + s->offset` can lead to a crash. Therefore, print the object's address in such cases.
Fixes: bb192ed9aa71 ("mm/slub: Convert most struct page to struct slab by spatch") Signed-off-by: Li Qiong liqiong@nfschina.com --- v2: - rephrase the commit message, add comment for object_err(). --- mm/slub.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-)
diff --git a/mm/slub.c b/mm/slub.c index 31e11ef256f9..8b24f1cf3079 100644 --- a/mm/slub.c +++ b/mm/slub.c @@ -1097,6 +1097,10 @@ static void print_trailer(struct kmem_cache *s, struct slab *slab, u8 *p) size_from_object(s) - off); }
+/* + * object - should be a valid object. + * check_valid_pointer(s, slab, object) should be true. + */ static void object_err(struct kmem_cache *s, struct slab *slab, u8 *object, const char *reason) { @@ -1587,7 +1591,7 @@ static inline int alloc_consistency_checks(struct kmem_cache *s, return 0;
if (!check_valid_pointer(s, slab, object)) { - object_err(s, slab, object, "Freelist Pointer check fails"); + slab_err(s, slab, "Invalid object pointer 0x%p", object); return 0; }